Fish is naturally low in sodium and easy to prepare. Grilling it takes just minutes, and it's one of the healthiest cooking methods out there. Marinate the firm-fleshed fish of your choice with olive oil, garlic and whole sprigs of fresh herbs such as rosemary, thyme and parsley. Put both the fish and seasonings on the grill, and as everything cooks, the stems of the herbs will impart a subtle smoky taste to the flesh. The final flavor flourish is a squeeze of fresh lemon juice over the food after you take it off the grill.